HP LJ P2055DN
Printer powers up, displays the HP logo and then goes to Initializing. The motor runs and the gears turn.
At that point, it flashes the power led and the attention led 4 times and is stuck in a loop. It never comes Ready.
The engine test will not run.
The formatter board has been replaced twice and the problem symptoms do not change.
The odds for getting the same error on the 2 replacement boards as the original board make me think that the formatter board is not the problem.
Possible fuser heater or fuser heat sensor seems like the next step.